Adverse Event Reporting: What You Need to Know

According the the United States Food and Drug Administration (FDA), all drug and device safety information is thoroughly vetted before a product gains approval. Unfortunately, even well-designed clinical studies can miss problems, meaning that some issues emerge only after a product has been released for public use. As such, it is important for all consumers to understand what constitutes an adverse event, how they are monitored, and how everyone can help protect public health by reporting the negative effects of drugs and medical devices.

What Is an Adverse Event?

An adverse event occurs when a patient encounters any undesirable experience associated with the use of a drug or medical device. They range from unconcerning to life-threatening, and they can even include events like changing the color of a person's urine. If you learned about allergies to specific antibiotics as a child, the hives you likely experienced after taking them would be considered an adverse event.

While adverse symptoms are typically associated with a particular drug or medical device, they may not necessarily be caused by the drug/device. Especially when the general population uses medical products, a number of variables can influence the symptoms experienced after using them, such as lifestyle, diet, other medical conditions, and environmental factors.

Some patients may face unintended side effects simply as a result of underlying conditions. For example, most patients who take gadolinium based contrast agents have no issues with it. But patients with impaired kidney function can develop a rare but serious condition known as gadolinium deposition disease (GDD), a fact that came to light only after the drug was used in the general population. Thus, the more information the FDA has about negative drug and device effects, the easier it is for them to discern which constitute legitimate new safety concerns and which do not.

While most negative side effects are on the less serious end of the spectrum, some, like GDD, can be quite dangerous. In order to prioritize them, the FDA has established a list of serious adverse events (SAEs) that should always be reported.

U.S. Food and Drug Administration Defined Serious Adverse Events

  • Death
  • Life-Threatening Event
  • Initial or Prolonged Hospitalization
  • Disability
  • Permanent Damage
  • Congenital Anomaly or Birth Defect
  • Required Medical Treatment to Prevent Permanent Damage
  • Other Important Medical Events

How to Report Adverse Events

Patients have no legal requirement to report adverse events, but healthcare providers and medical manufacturers are subject to mandatory reporting requirements. Medical product reports are submitted through the MedWatch Voluntary Reporting Form, and clinical vaccine reports go through the Vaccine Adverse Event Reporting System (VAERS).

We've created the guide below to make it easy to see where consumers can make reports.

FDA Adverse Event Reporting Guide for Consumers

Product Type What to Report How to Report
Prescription and Over-The-Counter Drugs, Biologics, Medical Devices and Combination Products Severe or unexpected side effects, especially those not included in the product label MedWatch Voluntary Reporting Form 3500B
Vaccines Any adverse side effect considered serious, even if possibly unrelated to the vaccine VAERS Form

Reports can also be sent to the manufacturer, and federal reporting regulations mandate that such reports are then shared with the FDA.

What Happens to Reports?

Once made, regulators at the Center for Drug Evaluation and Research (CDER) or the Center for Biologics Evaluation and Research (CBER) analyze all reports to determine which may legitimately be caused by the drug or device in question. Sometimes they find that the negative symptom occurred naturally or stemmed from some other cause. When the adverse effect seems to be caused by the medical device or drug, the FDA may follow-up with one of these options to protect public health and safety:

  • Request that the manufacturer completes additional safety studies.
  • Enforce a label change emphasizing the adverse event.
  • Ask the manufacturer to recall or entirely remove their product from the market.

Should I Really Report My Side Effect?

Not sure which side effects to report? Go ahead and check the safety information and label of the drug or device you suspect. If your symptom doesn't appear anywhere on the label, definitely make a report. If your symptom is on the label, it's still important to notify the FDA. Sometimes side effect frequency is underestimated in clinical trials. This kind of report can help both regulators and manufacturers update labeling information to more accurately represent side effect probability.

The more information regulators have about negative drug and device effects, serious and non-serious, the better able they are to protect the American people. If women had known they could voluntarily report their negative experiences with the Essure implantable birth control device from the outset, it may have been pulled from the market much earlier and prevented countless injuries.

Remember, adverse event reporting helps keep us all safe, and it's really easy to do. Just fill out the appropriate form at the applicable link below:

Drug and Medical Device Adverse Events: MedWatch Voluntary Reporting Form

Vaccine Adverse Events: Vaccine Adverse Event Reporting System

Where to Find Adverse Event Reports

Drug and device reports can be found in the FDA Adverse Event Reporting System (FAERS) Public Dashboard. Vaccine associated reports are kept separately with the Vaccine Adverse Event Reporting System Data Sets, but both are available online at all times.

Despite the easily available data, interpreting negative side effect reports can pose quite the challenge. It's important to keep in mind the following when examining FAERS or VAERS data:

  • Duplicate Reports
    The same event can be reported multiple times by patients, health professionals or facilities.
  • No Causal Relationship
    Reports do not necessarily mean the negative symptoms were caused by the drug or device mentioned.
  • Unvetted
    These reports are not verified.
  • Statistically Unhelpful
    It is impossible to determine the incidence of negative side effects in the United States (or anywhere else) based upon these reports.

Though these reports do come with limitations, they serve as the most effective way for regulators to learn of side effects and product safety concerns missed in preclinical studies. In one report, a device used to stop bleeding was shown to swell and damage the spinal cord. Just the one report provided enough information for regulators to determine that the product should not be used in or near the spine. The label was updated accordingly, protecting countless patients.

The FAERS and VAERS data sets provide a wealth of information, but it would be unwise for a patient to use either to modify their medications. These reports are better suited to informing conversations between patient and physician. Together they can ensure that all possible side effects have been discussed, allowing both healthcare providers and patients to weigh the risk/benefit ratio of any particular treatment.

Authored by Katy Moncivais, Ph.D.Medical Editor
Photo of Katy Moncivais, Ph.D.
Katy Moncivais holds a Ph.D. in Biomedical Engineering from The University of Texas at Austin. She’s an experienced Regenerative Medicine Consultant with a demonstrated history of working in the hospital & healthcare industry. Skilled in adult stem cells, medical devices, biomechanics, bacterial and mammalian cell culture, and regenerative medicine, she provides guidance on an array of topics affecting consumers. In her role at, Dr. Moncivais works alongside the writing and research staff to help deliver fact-based news stories to consumers. Her unique professional history alongside her rigorous educational background allows her to contribute to a variety of consumer-focused topics with a fresh perspective. In addition, Dr. Moncivais reviews portions of medically driven content to ensure scientific accuracy.
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